Sputtering target

Abstract

A sputtering target comprising a target material, wherein a sputtering face of the target material has a ramp provided to reduce a thickness of the target material at a position where erosion concentrates most intensively during sputtering.

The invention claimed is: 
     
       1. A sputtering target comprising a target material, wherein a sputtering face of the target material has a ramp provided, to reduce a thickness of the target material, at a region at a position of 80% or more depth against the deepest position of an erosion to be generated during sputtering, wherein the thickness of the ramp is 0.3 mm to 10 mm. 
     
     
       2. The sputtering target according to  claim 1 ,
 wherein the sputtering face has a circular shape, and 
 the ramp is formed at a position in a range of 60% or more and less than 90% of a diameter of the sputtering face so as to reduce the thickness of the target material toward a peripheral part of the sputtering face in the radical direction of the sputtering face. 
 
     
     
       3. The sputtering target according to  claim 2 , wherein the target material includes a flat circular first region positioned at a center of the sputtering face, a flat ring-shaped second region positioned around the first region, and a flat ring-shaped third region positioned around the second region,
 wherein the ramp exists between the second region and the third region, and a thickness of the third region is smaller than a thickness of the second region; 
 wherein the thickness of the third region is equal to or larger than a thickness of the first region and a diameter of the first region accounts for 14% or more and less than 60% of the diameter of the sputtering face; and 
 wherein an inner diameter of the third region accounts for less than 90% of the diameter of the sputtering face. 
 
     
     
       4. The sputtering target according to  claim 3 , wherein a ratio of the thickness of the third region to a ring width of the third region is in a range of 0.1 to 1.1. 
     
     
       5. The sputtering target according to  claim 4 , wherein the ratio is in a range of 0.1 to 0.6.